dennisdk2000
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I have recently finished reading Yeast: The Practical Guide to Beer Fermentation by Chris White and Jamil Zainasheff I would like to try my hand at freezing yeast at home, but as I don't have a background in Microbiology or similar there are a few things I'm unsure about:
Is there anywhere to buy cell culture supplies without breaking the bank? So far, the stuff I've seen is a bit pricier than I'd have liked! The protocol they suggest uses YPD broth, glycerol and ascorbic acid. Also, when looking at options, I'm not really sure what's required in terms of purity/grade etc. I understand that everything has to be sterile, but rather than buying sterile supplies (which I might struggle to keep sterile once opened as I don't have a laminar flow hood or the like), I thought I could sterilise media and glycerol myself, either by "autoclaving" in a pressure cooker, or by sterile filtering - is that a good method? Or will that turn out to be an expensive option? I remember sterile filtering things with a syringe a filter when working as a technician years ago, and as I only do small volumes, this was what I was planning on doing. Perhaps I should mention I live in the UK, but don't mind buying stuff from over-seas!
The protocol says to "...pick a culture and grow it in 10 milliliters of medium for 48 hours... move the 10 milliliters culture to a 40° F environment , and hold for another 48 hours, to encourage the yeast to build trehalose..." I assume this means picking a colony from a plate or slant and propagating it before proceeding. I intend to buy packages of liquid yeast, and split and freeze them. Should I still propagate the liquid yeast prior to freezing in order to build glycogen and trehalose? Or can I go straight to the next step? How many cells should I be using? Based on the cell count given by the manufacturer I can would out how much to use to equate "a culture".
If there are any other tips or advice anyone with a bit of experience in Microbiology can offer, it would be greatly appreciated! Thank you!
Dennis
Is there anywhere to buy cell culture supplies without breaking the bank? So far, the stuff I've seen is a bit pricier than I'd have liked! The protocol they suggest uses YPD broth, glycerol and ascorbic acid. Also, when looking at options, I'm not really sure what's required in terms of purity/grade etc. I understand that everything has to be sterile, but rather than buying sterile supplies (which I might struggle to keep sterile once opened as I don't have a laminar flow hood or the like), I thought I could sterilise media and glycerol myself, either by "autoclaving" in a pressure cooker, or by sterile filtering - is that a good method? Or will that turn out to be an expensive option? I remember sterile filtering things with a syringe a filter when working as a technician years ago, and as I only do small volumes, this was what I was planning on doing. Perhaps I should mention I live in the UK, but don't mind buying stuff from over-seas!
The protocol says to "...pick a culture and grow it in 10 milliliters of medium for 48 hours... move the 10 milliliters culture to a 40° F environment , and hold for another 48 hours, to encourage the yeast to build trehalose..." I assume this means picking a colony from a plate or slant and propagating it before proceeding. I intend to buy packages of liquid yeast, and split and freeze them. Should I still propagate the liquid yeast prior to freezing in order to build glycogen and trehalose? Or can I go straight to the next step? How many cells should I be using? Based on the cell count given by the manufacturer I can would out how much to use to equate "a culture".
If there are any other tips or advice anyone with a bit of experience in Microbiology can offer, it would be greatly appreciated! Thank you!
Dennis
